System of telegraphy.



PATENTED MAY 31, 1904. J. L.. GRBVBLING. SYSTEM OF TBLBGRAPHY. APPLICATION FILED APlhll, 1903.

U0 MODEL.

1 INVENTOH UNITED ST TES;

Patented May 31, 1904. I

PATENT OFFICE.

JOHN I CREVELING, on NEW YORK, N. Y.

, SYSTEM OF TELEGRAPHY.

SPECIFICATION formingpart of Letters Patent No. 761,450, dated May 31, 19Q4.

Application filed April 11, 1908. Serial No. 152,174. (No model.) i

To whom, it may concern.-

Be it known that I, J OHNL. CREvnLiNe, a citizen of the United States, residing at New York, county of New York, and State of New York, have invented new and useful Improve 1 ments in Systems of Telegr'aphy,as set forth in the following specification and drawings,

. forming a part thereof.

My invention pertains to that class of telegraphy or signaling systems commonly designated as wireless-telegraphy systems, in Wl'11Cl1 so-called Hertzian waves or oscillations are set up at a sending-station and detected ata receiving-station in such manner as to provide means conveying signals or messages. 1 Y

My invention has for its particular object to provide a signaling system or system of communication provided with a sensitive and positive detector in which the objectionable features of the so-called Branlycoherer or means employing the so-called imperfect contact as employed by Marconi are avoided, and l have produced a detectorof extremely ting of increased velocity in transmission as well as delicacy in operation. a

Referring to the drawings, Figure I- represents the transmitting-station, which may be of any desired character, aifording means to set up Waves or oscillations. For the purpose of illustration an ordinary secondarycoil and spark-gap apparatus are shown, in which 1 represents the induction-coil; 2, any suitable form of vibrator or current-interrupter in the primary circuit thereof. 3 represents the usual condenser as connected in shunt to-the breaker. 1 represents the battery in primary a circuit, which circuit is manipulated, as by key 5, for the transmission of signals. numerals 6 represent the discharge knobs and supports arranged to provide a spark-gap, as indicated at 7.. One of the knobs is grounded, as by the wire 8 and plate 9, While the other is connected, as by the wire 10, to the elevated capacity indicated at 11, a r Fig. 11 represents diagrammatically the receiving-station, in which 12 is the base of the detector, upon which is placed a suitable metallic conducting trough or receptacle 13. 14

The

represents an insulatingpost carrying the metallic'spring 15, provided with a head 16, through which is passed a conductor 17 adjustable therein, as by means of'screw 18. 19 represents an adjusting-screw, whereby the conductor 17 may be raised or lowered with regard to the receptacle" 13. -The de-. pressed portion of the member 13 is filled with a solution, preferablyvan electrolyte, as indicated at 20. 21 represents the battery,

the positive pole of which is connected, as by I the wire 24, to the spring 15, from which is .also led the wire 25 to earth, as indicated at '26.

The wire 23 connects the receptacle 13 with one of the terminals of the receiver or audible or visible indicator, in this instance shown as an ordinary Bell telephone-receiver,

the other terminal of which is connected to the negative pole of the battery 21. The

"wire 27 leads from the receptacle 1?) to the elevated capacity 28.

The normal operation of this system is substantially as follows, the various instrumentalities being considered as approximately in the-same positions occupied in the diagram.

By properly adjusting the position of the conductor 17 and proper manipulation of the adjusting-screw 19 the lower end of the conductor 17 may be brought in proximity to the "bottom of the cavity or depression in the receptacle 13,. and there-will be between these two members a thin layer of the solution or electrolyte, and if a proper battery 21 therefor bep'rovided a very feeble current will flow through this circuit, owing to the high resistance of the telephonic receiver, and by electrolytic action decrease the resistance of the gap between 17 and 13, apparently causindicated at 20.

ing a bridge of electrolytically-deposited metal in a finely-divided state across this space, giving the same a very low resistance. In this condition little or no electrolytic action will take place, insomuch as the detector will, so to speak, be internally short-circuited.

to speak, the instrumentality, causing the re sistance to have been reduced, such action of course raising the resistance or producing an equivalent effect in this circuit and causing a sound to be produced by the receiver 22,

which sound is sharp and distinct and readily applicable to a telegraphic code, and thereby providing means of transmitting intelligence across space.

The foregoing description of the operation of this system is given without the intention of confining the applicant to any theory or precise action taking place save that the resistance in the detector-circuit is increased or an action is produced which for this purpose is the equivalent of an increase in resistance by an action of the waves set up at the transmitting-station. Various metals have been used both for the conductor 17 and receptacle 13, and various solutions or materials have been used for the medium in contact with them, as However, as the particular materials to be used for these various instrumentalities form no part of my present invention, one combination only fulfilling the requirements of operating in accordance with this specification will be given, to wit: 17 may be made of copper, 13 may be made of lead, and 20 may be a weak solution of dilute sulfuric acid. Various other combinations may be used without varying from the scope of this invention, and I do not wish in any way to be considered as confined to the exact instrumentalities or materials shown in this application, which are indicated diagrammatically merely.

Having thus described my invention, what I desire to secure, and protect by Letters Patent, is as set forth in the following claims:

1. Means detecting Hertzian waves or oscillations comprising means maintaining a difference of potential, as a battery, a circuit containing this means and means lowering the resistance of this circuit by virtue of said difference of potential, and responsive to the action of said waves or oscillations.

2. In a system of transmitting signals across space the combination of means setting up electric waves or oscillations means controlling the production of said oscillations with means detecting said oscillations comprehending means capable of producing an effect upon the senses in a circuit comprising means maintaining a difference of potential and means increasing the resistance of said circuit by the action of the above-mentioned waves or oscillations, and adapted to diminish, or nullify, said increase, under action of said difference of potential upon cessation of theeflect of the waves, or oscillations.

3. Inasystem of transmittingsignals across space the combination of means setting up electric waves or oscillations means controlling the production of said oscillations with means detecting said oscillations comprehending means capable of producing an effect upon the senses in a circuit comprising means maintaining a difference of potential and means increasing the resistance of said circuit by the action of the above-mentioned waves or oscillations and means whereby the action caused by said waves is nullified by virtue of current caused by the said difference of potential upon the cessation of said waves or oscillations.

1. Means transmitting signals across socalled space comprehendingmeans setting up electric waves or oscillations means controlling the setting up of said oscillations in combination with means detecting said waves or oscillations comprehending a circuit including a receiver capable of causing an action upon the senses by decrease in current flowing therein and means setting up the difference of potential causing a current to flow therethrough and means reducing said current by the action of said waves or oscillations, and means tending to restore said current immediately upon cessation of the effect of the waves, or oscillations.

5. Means detecting electric waves or oscillations, comprehending a circuit containing means detecting changes of resistance in said circuit, combined with means increasing the resistance of said circuit under the effect produced by waves, or oscillations, and means in said circuit constantly tending to decrease the resistance in opposition to the elfect of the waves or oscillations.

6. A detector for electric waves, or oscillations, comprehending a receptacle of conducting material, a conducting-bath in said receptacle, a conducting member immersed in said bath, and means whereby electric waves, or impulses, vary the combined resistance of the above-mentioned instrumentalities in their re spective positions, as set forth.

7. A detector for electric waves, or oscillations, comprehending a receptacle of conducting material, a conducting-bath in said receptacle, a conducting member immersed in said bath, and means whereby electric waves, or impulses vary the combined resistance of the above-mentioned instrumentalities in their respective positions, as set forth, and means for adjusting the relations of said members.

8. A detector of electric waves or radiations comprising a plurality of conducting members, and an interposed electrolyte and means for adjusting the relations of the said conducting members to Vary the length of the circuit means maintaining a difieren'ce of potential, a conductor of the first class, and a conductor of the second class, and means for adjusting the effective length of the conductor of the second class.

In testimony whereof I have signed myn ame to this specification in the presence of two sub- 20 scribing witnesses.

JOHN L. CREVELING.

Witnesses:

W. H. S UIREs, M. B. RICHMOND. 

